California law does not allow state judges to sign off on warrants for federal agents, something that this particular FBI agent, Stonie Carlson, apparently did not know.

"But the two warrants were plagued by numerous errors, reflecting a pattern of systematic recklessness by law enforcement that militates in favor of suppressing the evidence (and against applying the 'good-faith exception' to the exclusionary rule)," US District Judge Vince Chhabria wrote in a July 3 order. "This ruling is published separately to put the relevant actors in the criminal justice system on notice that California law prevents state judges from issuing search warrants to federal law enforcement officers, which means that federal law enforcement officers are not permitted to execute such warrants."

The FBI put its Stingray to use to track cellphones used by people suspected of engaging in credit card fraud. The order [PDF] suppressing the evidence is an entertaining read -- one that doesn't pull any verbal punches excoriating the federal agents involved in this law-flaunting trip through a California courthouse.

FBI Agent Stonie Carlson brought two warrants to the Alameda County Courthouse -- one intimately familiar to the FBI. The judge signed off on the warrants despite state forbidding this practice. The FBI is also not allowed to use state judges for federal warrants, something Carlson apparently didn't know. As the order [PDF] points out, this ignorance alone might have been enough to salvage the warrants and evidence… if that's all there was to it.

A federal agent's mistaken belief that he could be issued a search warrant by a California state judge is likely not, on its own, a basis for suppressing evidence obtained during the search (at least before the publication of this ruling). That is arguably good faith negligence. But the two warrants were plagued by numerous errors, reflecting a pattern of systematic recklessness by law enforcement that militates in favor of suppressing the evidence (and against applying the "good faith exception" to the exclusionary rule).

But no good faith will be awarded here. Judge Chhabria wants to make it crystal clear no more of this "negligence" is welcome in his jurisdiction.

This ruling is published separately to put the relevant actors in the criminal justice system on notice that California law prevents state judges from issuing search warrants to federal law enforcement officers, which means that federal law enforcement officers are not permitted to execute such warrants.

As was noted earlier, state/county judges can issue certain warrants to federal and local law enforcement. But only local law enforcement is allowed to execute search warrants issued by local judges. If a federal agent wants to engage in a search or an arrest, they need to get their warrants approved by federal judges. The DEA's inability to follow California law has cost it a few cases over the years. The FBI is going to have the same problem if it doesn't train its agents correctly.

Even if it was a lapse in training, Judge Chhabria isn't interested in forgiving Agent Carlson for his agency's failings. This results in one of the harsher bench-slaps handed out to a federal agent.

At the evidentiary hearing, Carlson claimed that his decision to seek the warrants from state court judges, rather than a federal magistrate judge, was based partly on training his colleagues received from that office. This statement by Carlson may or may not accurately reflect whatever his colleagues learned or told him, since Carlson's general conduct in this case, as well as his testimony at the evidentiary hearing, shows that he is neither well-trained nor particularly concerned with complying with the law in conducting his enforcement activities.

The ruling isn't just issued for the FBI's benefit. It's also there to tell state judges to do their job correctly. But it cuts the judge in this case some slack, but only by suggesting Agent Carlson may have muddied the warrant water deliberately.

[T]he two state court judges who issued the warrants may have been unaware of the legal limits on Carlson's ability to insert himself into the state criminal justice system. The record is not clear on this point. As discussed in the separate unpublished ruling, although the state court judges likely should have known that Carlson was seeking authorization for himself and other federal officers to execute the searches, it is possible they were misled by the paperwork Carlson submitted to them.

The FBI is finally using warrants for Stingrays -- just as the DOJ stated back in 2015. Agents are just doing it as incorrectly as possible, which isn't a huge improvement. Considering the way this one was botched, Agent Carlson may as well have not even bothered filling out an affidavit.